Popular metric, commonly known as pop met, single row deep groove ball bearings are one of the most common types of ball bearing in use this is down to their versatility. They are simple in design, suitable for high speeds, non separable, are very robust in operation and require very little maintenance. Deep raceway grooves and the close conformity between the grooves and the balls enable deep groove ball bearings to accommodate axial loads in both directions, even at high speeds.

A shielded ball bearing has two metal shields, one on each side of the ball bearing between the inner and outer races. This offers the ball bearing some protection from outside contaminants such as dirt and moisture, as well as protection from light mechanical damage. The metal shields also retain the pre-filled grease within the ball bearing ensuring that it stays lubricated for life.